1. Field of the Invention
The invention relates to a field-effect-controllable power semiconductor component with a semiconductor body and a multiplicity of mutually parallel-connected transistor cells disposed in at least one cell field.
In order to protect such a semiconductor component which, for instance, may be a power MOSFET or an IGBT, from overload, it has been proposed, for instance in Published European Patent Application 0 224 274, that a temperature sensor be disposed in the center of the semiconductor body. The temperature sensor is seated in a recess of a field of transistor cells that are connected parallel to one another.
If the load is entirely or partially short-circuited, then the semiconductor body heats up because of discontinuities at preferential local points. After a time, which is determined by a transient thermal resistance between those points and the temperature sensor, the sensor detects the excess temperature and switches the power semiconductor component off.
In high-power semiconductor components, the area of the semiconductor body must be made greater. However, as the area of the semiconductor body increases, the likelihood that the power semiconductor component will be destroyed before the temperature sensor responds, increases as well.
2. Summary of the Invention
It is accordingly an object of the invention to provide a field-effect-controllable power semiconductor component with a plurality of temperature sensors, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type in such a way that the likelihood of destruction from an overload is drastically reduced.
With the foregoing and other objects in view there is provided, in accordance with the invention, a field-effect-controllable power semiconductor component, comprising a semiconductor body; at least one cell field; a multiplicity of mutually parallel-connected transistor cells disposed in the at least one cell field; and at least two temperature sensors integrated in the semiconductor body and disposed at different locations from each other on the semiconductor body.
In accordance with another feature of the invention, the at least one cell field includes at least two spaced-apart cell fields on the semiconductor body, the transistor cells are disposed in the at least two spaced-apart cell fields, and each of the cell fields includes a respective one of the temperature sensors.
In accordance with a further feature of the invention, the temperature sensors are disposed at a location of the cell fields where a highest temperature is to be expected.
In accordance with an added feature of the invention, the cell fields are spaced apart from one another by a distance being on the same order of magnitude as a thickness of the semiconductor body.
In accordance with an additional feature of the invention, there are provided peripheral structures each surrounding a respective one of the cell fields.
In accordance with yet another feature of the invention, there is provided a trigger circuit furnishing a control voltage for the semiconductor component and reducing the control voltage as long as at least one of the temperature sensors outputs a signal.
In accordance with yet a further feature of the invention, there is provided a trigger circuit furnishing a control voltage for all of the cell fields and reducing the control voltage for all of the cell fields as long as at least one of the temperature sensors outputs a signal.
In accordance with a concomitant feature of the invention, there are provided trigger circuits each furnishing a control voltage and reducing the control voltage for a respective one of the cell fields as long as one of the temperature sensors associated with the one cell field outputs a signal.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a field-effect-controllable semiconductor component with a plurality of temperature sensors, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.